1. Technical Field
The present disclosure relates to an electrode assembly that allows a user to cut tissue. More particularly, the present disclosure relates to a blade assembly having a unique electrode configuration assembled with geometrical variations that vary current densities and electrical fields.
2. Background of Related Art
Many surgical procedures are enhanced by the use of an electrosurgical instrument for cutting, spot coagulation, point coagulation, and sealing of tissue during an operation. For example, thermal energy may be used in general surgery as a substitute for a scalpel to assist in the control of blood flow. Procedures where electrosurgical devices are used include open and laparoscopic/minimally invasive general surgery as well as specialty areas, such as arthroscopic surgery, orthopedic surgery, cardiovascular surgery, cosmetic/reconstructive surgery, neurosurgery, and urologic surgery. Application generally includes manually contacting the electrosurgical instrument directly to the appropriate area of tissue.
Various surgical instruments are known for treating tissue. For example, surgical instruments used for tissue division, dissection, ablation, or for arresting blood loss and coagulation are well-known. In a particular application, for example, a coagulation instrument has an electrode used in conjunction with a heated probe to arrest bleeding. However, since the probe must come into close contact with the tissue, the probe may adhere to the tissue during probe removal and possibly cause repeat bleeding.
As can be appreciated, the overall success of creating an effective cut with cutting instruments is greatly reliant upon the user's expertise, vision, dexterity, and experience in judging the appropriate force, and length of reciprocation of a knife or electrosurgical cutting device to uniformly, consistently and effectively cut tissue along an ideal cuffing plane. Thermal spread, charring, aberrant current densities and electrical fields may reduce the overall success rate of a cut by diminishing the surgeon's ability. Known electrosurgical cutting instruments are problematic for they do not attempt to reduce and/or limit undesirable visual effects such as thermal spread, charring, or take into account aberrant current densities and/or electrical fields which may decrease the accuracy of the cutting device. Moreover, energy-based medical devices often are limited by the placement and geometries of the electrodes on the device, an integral element of their use. As electrosurgical instruments are often manually applied to the tissue during the surgery to effect a cut, precise control by the surgeon, taking into account the placement and geometries of the electrodes on the device, is required. In known devices, placement and geometries of the electrodes are problematic in that they may increase the length of the procedure (particularly when cutting a significant number of vessels) and/or may contribute to imprecise separation of the tissue along the cutting line due to the misalignment or misplacement of the severing instrument along the center of the tissue cut.
Some prior art devices include an electrosurgical instrument having a nonconductive handle that holds a blade assembly. The blade assembly includes a plurality of electrodes and an insulation member separating the electrodes. An active center electrode of specified thickness with a recessed tip is mounted to an extruded insulation member so that it extends outwardly from the insulation member to form a cutting edge. However, such a device limits the surgeon's ability to visually and manually regulate the placement and amount of force of the blade assembly to the tissue. Moreover, such a device does not attempt to vary a tissue cut by providing an electrode configuration that modifies current densities and electrical fields around the device.
New electrosurgical blades having different placement and geometries of the electrodes are continuously sought after to satisfy different surgeons, as well as alter aberrant current densities and/or electrical field formation around the device.